Page "Spam Prevention Early Warning System" Paragraph 12

SPEWS criteria was based on " spam support "; That means that when a network operation provides any services to the identified spammers, the resources involved were listed.

For instance, part of an ISP's network may have been listed in SPEWS for providing DNS service to a domain mentioned in a piece of e-mail spam, even if the messages weren't sent from said provider's mail servers.